The Convention of "argv[0] = Name of Executable"
Question:
When passing arguments to the main function in C or C programs, does argv[0] always contain the executable's name? Or is this merely a common practice that may not hold true in all cases?
Answer:
According to the ISO C11 standard:
If the value of argc is greater than zero, the string pointed to by argv[0] represents the program name; argv0 shall be the null character if the program name is not available from the host environment.
Therefore, it is not always guaranteed that argv[0] will represent the exact name of the executable. Rather, it is an implementation-defined value that is provided by the host environment and may not necessarily be the executable's filename.
The ISO C standard further states that if argc is greater than zero, the array members argv[0] through argv[argc-1] will contain pointers to strings with implementation-defined values determined by the host environment before the program starts.
This means that the value of argv[0] is not explicitly specified by the standard, allowing for variations in behavior across different platforms and operating systems.
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